Electron mobility of 4,7-diphyenyl-1,10-phenanthroline estimated by using space-charge-limited currents

Abstract

The electron mobility of 4,7-diphyenyl-1,10-phenanthroline (BPhen) at various thicknesses (50–300nm) has been estimated by using space-charge-limited current measurements. The measured bulk mobility is in excellent agreement with results from time-of-flight method. It has been observed that the electron mobility of BPhen approaches its true value when the thickness is more than 150nm. The estimated electron mobility of BPhen at 300nm is found to be 3.4×10−4cm2∕Vs (at 0.3MV∕cm) with weak dependence on electric field. For thickness typical of organic light-emitting devices, the electron mobility of BPhen is also investigated. At the request of the authors, this article is being retracted effective 31 May 2011.